March 25 – Aaah-Choo!

Today’s factismal: It can take two years for a juniper “berry” to ripen.

When is a berry not a berry? When it is actually a pine cone! The juniper is an evergreen, closely related to the redwood, cedar, and pine tree. But unlike its kin, the juniper produces cones that are filled with starch and flavor covering an indigestible seed. Where redwoods and pines rely on dry winds to disperse their seeds, the sweet and fleshy juniper cone attracts birds and other wildlife. They snack on the cone and disperse the seeds (along with a little fertilizer) as they gad about. This successful adaptation has helped the juniper to develop more than fifty different species, spread over five continents. Their native hardiness has also helped; individual junipers have been known to live as long as 2,000 years in harsh, forbidding conditions.

The world's largest juniper lives in Utah (Image courtesy Juniperus of the World)

The world’s largest juniper lives in Utah (Image courtesy Juniperus of the World)

Though juniper leaves is used in food preparation and the wood is commonly found in furniture, the most popular part of the juniper tree is indisputably the “berry”. When it is green, this little morsel is used to flavor beer and gin; it actually gives gin its name (from the Dutch “jenever”, which means “juniper”). And when ripe, it is added to wild game and birds in order to offset the gamy taste by giving them a sharp, clean flavor. And the berries of some junipers are eaten as a snack, though experts do not recommend grabbing those in the wild as other species’ berries can have a diuretic effect.

The "berries" of the common juniper (Image courtesy Wikipedia)

The “berries” of the common juniper (Image courtesy Wikipedia)

The time it takes to produce a berry depends on the juniper species. Though some species can produce a ripe berry, ready to grow into new junipers, in as little as six months, most take 18 months to mature. But the Syrian juniper takes two years to create a ripe berry, thanks to the area’s dry conditions; the Syrian juniper is also the tallest of the junipers.

Like all of its relatives, the juniper reproduces sexually by releasing pollen. The male cones shed pollen into the air in the early to mid-spring; it is airborne and lands on female cones that then develop into berries. For most people juniper pollen is only a minor annoyance that coats their cars and turns the sky a dusky orange. However, there are a few who are allergic to the pollen; for them, junipers are more bane than blessing. If you’d like to help these folks and the scientists who are studying juniper, then head over to the Juniper Pollen Program and tell them when the junipers in your area start to shed pollen.
https://www.usanpn.org/node/2434

March 24 – To Hades With You!

Today’s factismal: It would take 5.6 planets the size of Pluto to make one Moon (and 169 to make one Earth).

In just under 90 days, we will make a dream come true. For the first time, we will have visited every “traditional planet” with a probe. Back in 1964, planetologists noticed that the planets would be in the perfect positions to visit them all in a “Grand Tour” with four probes. Two would would be launched in 1976 and 1977 and fly by Jupiter and Saturn before heading out to Pluto. Another two would be launched in 1978 and would fly by Jupiter, Uranus, and Neptune. At each planet the probes would swing in close and use the slingshot effect to throw them out to the next planet. But that dream died thanks to tight budgets and a lack of public interest.

Or rather, it almost died. The planetologists salvaged the idea and changed the Grand Tour into a Greatest Hits voyage to Jupiter, Saturn, Uranus, and Neptune in what became known as the Voyager Program. These were the last of the great exploration probes; after they passed by Neptune, NASA turned its attention to Mars and Venus which were much closer and cheaper to visit. With a regretful wave, the planetologists settled for studying Pluto via telescope. And they discovered some amazing things.

A plot of planetary size versus density. Notice how Pluto ends up with the junk.

A plot of planetary size versus density. Notice how Pluto ends up with the junk.

Pluto and her five moons (Image courtesy NASA)

Pluto and her five moons
(Image courtesy NASA)

The first thing that they discovered was that instead of being as large as the other outer planets, Pluto was just a tiny thing. With every new measurement, Pluto shrank from being as big as Jupiter (a thousand times as massive as Earth) to being the size of Earth to being so small that it would take five of them to equal the Moon’s mass. Excitingly, they also discovered that Pluto two distinct hemispheres with one side of the planet being much brighter than the other. They also found that Pluto has five moons of its own (the most recent pair being discovered in 2011 and 2012). And with each new discovery, our regret at not visiting this fascinating planet grew.

 

The New Horizons spacecraft will meet Pluto in two years (Image courtesy NASA)

The New Horizons spacecraft will meet Pluto in two years
(Image courtesy NASA)

The moons of Pluto (Image courtesy NASA)

New Horizons’ path to the stars by way of Pluto
(Image courtesy NASA)

And it grew until finally NASA agreed to send a small probe rocketing past the planet. Originally called the Pluto Express (both for how fast it will go past the planet and for how quickly it was built), the probe is now known as the New Horizons. Launched nine years ago, the probe will reach Pluto in about 90 days. But the probe will be going so fast that it can’t stay to image the planet; instead, it will speed past and head on out to the outer parts of the Solar System.

And that’s where the citizen science starts! Because the data will be coming in hot and heavy during the few days when the probe is close enough to get a good view of the planet and its moons, the scientists are lining up the names for those things now – and they want your help! They have set up a web form for us to vote on various names for Pluto’s features and to propose names of our own. Of course, even if a name is popular, that’s no guarantee that it will be used; the IAU (the folks who don’t know what a planet is) overruled the name picked by the discoverer of Pluto’s fifth Moon (Vulcan) for one of their own (Kerberos).  But it will still be fun to name the features and learn more about this amazing planet as New Horizons makes a fifty-year old dream come true in three months. For more information, zoom on over to:
http://www.ourpluto.org/vote

March 14 – Completely Normal

Are scientists normal? In today’s Secret Science Society adventure, Peter and Mary discover what the word means to scientists and why math can be important!

It was another typical Monday afternoon. Peter and Mary had finished lunch and were heading toward their favorite class. They didn’t like science class just because they wanted to be scientists; they also liked the way that their teacher, Mr. Medes, always managed to give them an interesting experiment to do. As a result, they frequently tried to predict what the experiment would be while they ate lunch. Today’s discussion had spilled over and continued as they walked to class.

“Well, it is Monday, so we know that it will be about math,” Mary said.

“Sure, but that doesn’t narrow it down much. Remember last week, when he had us coloring maps all class period?” Peter replied.

“And the week before, when we played with clay,” Mary said as they came to the classroom door. “Well, there’s only one way to find out – let’s go ask Mr. Medes!”

Mr. Medes was waiting for the class as they filed in and found their seats. As soon as all thirty-two students had come in, he started in on his lesson for the day.

“Welcome, welcome! Today is Monday, and that means math! For today’s lesson, we’re going to follow in the footsteps of that great gambler, Pascal. We are going to flip coins!”

“What does gambling have to do with math?” Peter asked.

“Believe it or not, most of the early work in statistics was done by Pascal and other gamblers as they sought a way to make more money. Pascal even invented a gambling machine that we know as the roulette wheel; he did it to see if he could create a perpetual motion machine. Instead, it turned into a perpetual money machine. But we won’t need anything that fancy today. We just need pennies.” As he said that, Mr. Medes passed out a penny to each of the students.

“Now, this is a very simple experiment. What we are going to do is flip the coins. If they are ‘fair coins’, which means if they are evenly balanced, then about half of them should come up heads and half should come up tails. Ready? Everybody flip!”

Suddenly the air was full of flipping coins. When the coins had stopped flipping, Mr. Medes asked for a show of hands from those who had heads.

“OK, we had 17 heads and 15 tails,” he said. “Let’s try that again, just to make sure that wasn’t a fluke.”

They repeated the test four more times, getting about the same distribution of heads and tails each time. Mr. Medes wrote 32 on the board then wrote the last result (14 heads and 18 tails) below it before turning back to the class.

“Good!” Mr. Medes said. “That proves that these are fair coins. We got about half heads and half tails each time, and everyone got a different set of heads and tails. But that raises an interesting question. What do you think would happen if we flipped the coins twice and kept track? How many times would we get either two heads or two tails in a row?”

“Well, you’ve got a fifty-fifty chance of getting heads after a tails, so you’d get it about half the time,” Mary said. “There are thirty two of us, so there’d be sixteen people with two heads or two tails.”

“No, you’re wrong,” Peter said. “You’ve only got a fifty-fifty chance of getting heads or tails on the first flip, so there should only be half as many. We’d have eight people with two heads or two tails. Everyone else will have a head and a tail or a tail and a head.”

“Well, there’s only one way to solve this problem,” Mr. Medes said. “Everyone take out a piece of paper and pencil to record your observations. Flip the coin and write down if it was heads or tails, then do it again.”

What do you think will happen? Do the experiment!

 

 

 

 

For a moment, the classroom was silent as everyone flipped their coins and wrote down the results. As soon as the last penny was put down, Mr. Medes spoke up again.

“OK, how many of you got two heads?” Nine hands went up, and Mr. Medes wrote that on the board. “How many got two tails?” Seven hands went up; Mr. Medes once again recorded the number, then put ‘16’ between them saying “And that leaves 16 people with either a head and a tail or a tail and a head.”

“Where did I go wrong?” Peter asked. “There should have been half that many!”

“Actually, you fell into the same trap that frustrated many of the mathematicians who discovered these rules. They forgot that everyone gets either a head or a tail for their first flip and that the real question is how many people will get a second head or tail. We can write it in math this way:”

Turning to the board, he drew

Second flip

Heads (F) Tails (T)
First Heads (F) FF FT
Tails (T) TF TT

“Hey! That looks like the truth tables my mom uses when she programs!” Peter said.

“That’s right; this branch of math lies at the intersection of programming and statistics. It is also useful in genetics and many other fields. If you count it up, you’ll see that there are two boxes where you get a mixed result and two where you get a ‘pure’ result. So, if you had written it down like this, you’d have known the right answer without needing to do anything more. So – how can we decide how many ‘pure’ results we’ll get if we flip the coins three times?”

“We make another truth table!” Peter said.

“Right,” Mr. Medes replied as he drew a table on the board.

Next flip

Heads (F) Tails (T)
Earlier flips FF FFF FFT
FT FTF FTT
TF TFF TFT
TT TTF TTT

“We’ve got eight possible outcomes, and two of those are ‘pure’. So we should get one eighth of thirty two, or four, people with three heads in a row and the same number of people with three tails in a row; that means we should have eight ‘pure’ results. Now let’s flip the coins and see what happens. After you’ve flipped, raise your hand is you have three in a row of the same, heads or tails.”

Everyone again flipped their coins. The class looked around and burst into smiles as seven people raised their hands.

“Why didn’t we get exactly eight?” Mary asked, with a puzzled look.

“Because this is statistics, which works best for a large number of flips. If we had 320 people flipping the coins, we’d probably get somewhere between 75 and 85 pure results. If we had 3200 people flipping coins, we’d get somewhere between 780 and 820 pure results. As you flip the coin more often, random errors even themselves out and you come closer to the true value. Let’s try an experiment to see why. Mary, if you flip a coin, what are the odds of it coming up heads?”

“It will be heads half the time,” she replied.

“Right. Now Peter, flip your coin and tell me what it shows.”

Peter quickly flipped his coin. “It came up tails!”

“Now that doesn’t mean that Mary was wrong. What it means is that you don’t have enough flips, what a statistician calls ‘a significant population’, to decide what the odds are. The only way to tell the odds is to flip a coin a lot of times. And the more times you flip it, the bigger the population and the less chance that some error has crept into your results. As a matter of fact, a mathematician named John Kerrich tossed a coin 10,000 times while he was being held as a prisoner of war by the Nazis. He got heads 5,067 times and tails 4,933 times. If he had only flipped it once, he would have only gotten a head or a tail, just like Peter did. So bigger is better in statistics.”

At that point, the bell rang and Mr. Medes said “Don’t flip out – I’ll see you tomorrow for more science!”

March 15 – Per Aspera Ad Artibus

Today’s factismal: Apollo 15 left a sculpture on the moon in honor of fallen astronauts.

There’s no getting around it; exploration is a risky business. And space exploration is no exception. We’ve sent some 536 people into space (along with four monkeys, a dog, and a whole bunch of fish) and eighteen of them have died in the attempt while another eight died preparing for the flight.  And even when they aren’t preparing for a trip into space, astronauts live dangerous lives, flying small aircraft, traveling long distances by car, and working with politicians. So it should come as no surprise that there are memorials to fallen astronauts all around the world. But what may come as a surprise that there is a memorial to fallen astronauts on the Moon.

A tree in the astronaut memorial grove at Johnson Space Center (My camera)

A tree in the astronaut memorial grove at Johnson Space Center
(My camera)

When the crew of Apollo 15 left for the Moon, a total of fourteen astronauts had died, either in space or on Earth. And so David Scott, the commander of Apollo 15, decided to create a memorial on the Moon. He worked with Paul Van Hoeydonck, a Belgian artist who was well known for his prints, to create a small figurine of an astronaut. Because the fallen astronauts included people from many races and both sexes, the figure was made so that it didn’t have an identifiable gender or race (not that these are visible in a spacesuit). In addition to Van Hoeydonck’s sculpture, Scott created a small plaque listing the 14 who had died. And when the crew of Apollo 14 got to the Moon, they created a memorial with the plaque and sculpture near Hadley Rille, where it remains to this day.

The Fallen Astronaut Memorial on the Moon (Image courtesy NASA)

The Fallen Astronaut Memorial on the Moon
(Image courtesy NASA)

Because the memorial is so small, the only way to see it would be to actually visit Hadley Rille. If you can’t wait for the next flight, you can still explore the Moon and find lots of other interesting things. To learn more, head over to the Moon Zoo where you can look at original NASA images and help classify the things you see:
http://www.moonzoo.org/

March 12 – What A Drip!

Today’s factismal: Not all drains lead to the ocean.

If you’ve looked at a storm drain cover lately (or watched Finding Nemo), then you’ve probably seen the warning on it: “This drain leads to the sea”. And, in 82% of the spots on land, that warning would be correct; those storm drains do lead to the ocean, eventually. They lead to creeks that drain into rivers that drain into other rivers that drain into the sea. But in about 18% of the cases, the creek leads to a river that leads to a lake that leads nowhere; it is an endorheic (“flows inside”) basin. When water and other stuff is dumped into that storm sewer, it flows downhill until it gets trapped in a lake. At the lake, the water evaporates away, leaving behind an increasingly salty (and, in some cases, polluted) body of water.

The Great Salt Lake is an endorheic watershed (My camera)

The Great Salt Lake is an endorheic watershed
(My camera)

This happens in the Dead Sea, the Caspian Sea, Laguna del Carbon, and the Great Salt Lake. These “terminal lakes” receive the water from everywhere within their drainage basin (also called a catchment or watershed), just as rivers in other watersheds eventually lead to the oceans. But in both cases, the quality of the water has a strong influence on what can live in the watershed. The abundance of fertilizers and silt provided to the Gulf of Mexico by the Mississippi River watershed creates an annual dead zone where fish cannot live; this then reduces the number of fish available for fishing and recreation. Similarly, the continuing shortage of water in the Colorado River has created hypersaline conditions in the Gulf of California that threaten the safety of gray, blue, and finback whales that spend the winter there.

This is not how you clean up a river (My camera)

This is not how you clean up a river
(My camera)

Though it may seem like the problem of cleaning up watersheds is too big to be tackled, the opposite is true. That’s because each big watershed is made up of smaller watersheds. The Gulf of Mexico gets water from the Mississippi River watershed, and the Mississippi River watershed gets water from the Arkansas River, Ohio River, and Missouri River water sheds. And the Ohio River watershed gets its water from the Allegheny and Monongahela River watersheds. And the Monongahela River watershed in turn gets its water from the Youghiogheny, Cheat, and Tygart River watersheds. And each of those watersheds can be further sub-divided into smaller rivers and creeks until you finally arrive at something small enough to clean up.

If you’d like to take part in cleaning up a watershed near you, then there’s no time like the present. Use one of the links below (or google for your own watershed) and get cleaning!


Great Swamp Watershed Association http://www.greatswamp.org/
Hudson River Estuary Program and Scenic Hudson http://www.dec.ny.gov/lands/4920.html
Kentucky River Watershed Watch http://www.uky.edu/OtherOrgs/KRWW/
Klamath Riverkeeper http://www.klamathriver.org/
Loudoun Stream Monitoring http://www.loudounwildlife.org/Stream_Monitoring.htm
Master Watershed Steward program (Arizona) http://cals.arizona.edu/watershedsteward/
Missouri Stream Team Program http://www.mostreamteam.org/
OPAL Water Survey http://www.opalexplorenature.org/WaterSurvey
RiverSweep (Ohio River) http://www.orsanco.org/sweep
Shermans Creek Watershed Monitoring Program http://www.shermanscreek.org/monitoringprogram.htm
Watershed Watch http://www.mywatershedwatch.org/
Willamette Riverkeeper Volunteer Water Quality Monitoring http://www.willamette-riverkeeper.org/WRK/waterquality.html
Wisconsin Stream Monitoring http://watermonitoring.uwex.edu/wav/monitoring/
WV Save Our Streams Program http://www.dep.wv.gov/WWE/getinvolved/sos/Pages/default.aspx
Yuba River Water Quality Monitoring http://yubariver.org/river-monitoring/

March 10 – Ice, Ice, Baby

Today’s factismal: As a glacier melts, it makes sounds that are louder than a chainsaw.

Though landlubbers may think of the ocean as being silent, seafarers know the truth. As early skin-divers and scuba explorers discovered, the ocean is full of sounds ranging from the continual grinding of parrot fish jaws as they eat the coral reefs around them to the throbbing booms made by drum fish as they beat their swim bladder with their abdominal muscles. And perhaps the best known example of ocean sounds are the various calls of the whales, from the friendly bottlenose dolphin’s whistles and clicks as it searches for food to the blue whale’s explosive shouts that cover half the ocean.

This parrot fish is actually pretty noisy (My camera)

This parrot fish is actually pretty noisy
(My camera)

It isn’t only critters that make noise in the water. Volcanic eruptions from the mid-Atlantic ridge and mid-Pacific seamounts hiss and sputter as the hot rock is suddenly quenched by the ice-cold water. Landslides along the continental shelves rumble threateningly as they dump tons of sediment and nutrients into the benthic ocean. Earthquakes fill the water column with a rolling thunder. And, surprisingly, even the glaciers add their soupçon of susurrus to the mix. You see, glaciers are formed when snow piles up faster than it can melt. As the snow piles higher and higher, it squeezes the individual snowflakes into a solid mass of ice. During the process, most of the air is squeezed out, but small bubbles can get trapped.

This is where the glacier meets the sea (My camera)

This is where the glacier meets the sea
(My camera)

If the glacier is on a slope that heads down toward the ocean, it will slide downhill and create what is known as a tidewater glacier. The weight of the ice mass up high in the mountains pushes the glacier oh so slowly out into the water, where it breaks off in bits. But, because the water is slightly warmer than the glacier, the ice at the bottom of the glacier melts. As it melts, it releases those air bubbles that were trapped so long ago. And those suddenly freed bubbles spring into a near-perfect sphere with a sudden “gloing!” of freedom. When enough of those bubbles pop open, it creates a 120 dB ruckus that is louder than a chainsaw!

A glacier calving; this isn't the noisy part! (My camera)

A glacier calving; this isn’t the noisy part!
(My camera)

Now the interesting thing about that sound is that it isn’t all bad. Seals and sea lions like to dive near glaciers, looking for fish to eat. And orcas like to dive near the seals and sea lions, looking for something to eat. But where seals use their eyes and whiskers to search for food, orcas use sound; like other whales, they send out a sonar beam that gets reflected off of things nearby helping the orca to locate a likely snack. But the constant noise of the glaciers makes it hard for the orcas to hear the reflected sound of their sonar; like someone trying to whisper in a rock concert, it just doesn’t work very well.

An orca's favorite snack (My camera)

An orca’s favorite snack
(My camera)

If you’d like to learn more about how orcas use sound to track their prey (and maybe even use the orcas’ own sounds to track them!), swim over to Orcasound.net:
http://www.orcasound.net/

March 7 – Seven Impossible Things

Ah, Saturdays! Is any day better? You get to sleep late, you get to watch cartoons, and (best of all) you get another Secret Science Society adventure! Today, Mary and Peter discover that there are somethings that man is not meant to know…

Most days, Peter and Mary got along well together. They both liked the same things, and they both wanted to be scientists. But every once in a while, they would fight. And, as is often the case with friends, when they did fight it was usually about something stupid. Today was no exception.

“There is so!” Mary shouted.

“No there isn’t!” Peter insisted. “There isn’t anything that is impossible!”

Attracted by the noise, Peter’s mother came into the den. “What is all the fuss about?” she asked.

“Tell Mary that there isn’t anything that’s impossible!” Peter demanded. “We might not be smart enough to figure it out, but there is always a way to do anything.”

“It is true that we’ve learned how to do a lot of things that people used to think were impossible,” Peter’s mother said. “We can fly faster than the speed of sound; there’s even been a car that drove that fast. We can orbit the Earth, and cure many diseases, and feed billions where millions used to starve.”

“See!” Peter interjected.

“Ah, but maybe there are some things that are impossible,” Peter’s mother continued. “Let me give you an experiment to do on impossibility.”

At that, both Peter and Mary perked up. Doing experiments was one of their favorite activities.

“Let me borrow the chalk and let’s go out to the sidewalk.” Picking up the chalk, Peter’s mother led them all to the sidewalk. “OK, here is the problem. Let’s pretend that the sidewalk is a river. In it are two islands, here and here.” Quickly, she sketched in two large ovals in the middle of the sidewalk. “Now on the big island, there are five bridges. Two go to the east side of the river,” she paused to sketch in two bridges leading to the lawn closest to them. “Two more go to the west side of the river,” she again paused to sketch in two more bridges leading to the lawn on the other side of the sidewalk. “And one goes to the little island. But it also has a bridge going to the east side of the river and another going to the west side.” She finished drawing the last three bridges and stood up. “Now here’s the challenge: Can you walk over all seven bridges without having to walk over any bridge twice? Is it possible to walk over all the bridges just once?”

The bridges

The bridges

“No way!” Mary said. “That’s impossible!”

“There’s no such thing,” Peter insisted. We just haven’t figured it out yet!”

“Well, I’ll be inside working on my exoplanet research,” Peter’s mother said. “Come and get me when you figure it out.”

As she walked into the house, Peter and Mary turned to the sidewalk and started trying different paths.

What do you think will happen? Do the experiment!

 

 

 

 

After about an hour, the two crept back into the house and found Peter’s mother staring intently over light curve data from the latest astronomy satellite.

“I give up,” Peter said. “How do you do it?”

“That’s easy,” his mother replied. “You don’t. This is a famous mathematics problem known as the Königsberg Bridges Problem. You see, in Germany, in a little town called Königsberg, they actually have seven bridges laid out just the way we drew them on the sidewalk. And people used to spend their Sunday afternoons trying to walk over all of the bridges exactly once.”

“This must have been before television,” Mary said.

“Yes, there wasn’t much else to do on Sundays back then. Now, to solve the problem a smart guy by the name of Euler decided that it was much too tiring to walk. Instead, he drew the problem as a bunch of dots connected by lines. There was one dot for the east side, one for the west side and one for each island. And each bridge was a line connecting the dots to each other.”

Peter’s mother turned over a scrap piece of paper and sketched out the diagram.

Euler's solution

Euler’s solution

“Now, Euler simply counted the number of lines leading to each dot. The only way that you can cross all of the bridges only once is if there are no dots with an odd number of lines, or if exactly two dots have an odd number of lines.”

“But we have four dots with an odd number of lines, so that’s impossible.” Peter said.

“Right. The neat thing about this is that highway engineers still use it to help design new interchanges. And computer engineers use it to design computer circuits.”

“So even though it is impossible, it is useful!” Mary said.

“That’s right. And if you’d like a real challenge, spend some time figuring out how many bridges you’d have to add to make the walk possible, and where you’d put them.”

With that, the two headed back out to the sidewalk to build some bridges.